Patent GB-491066-A (GB)
Abstract: 491,066. Calculating - apparatus. CHICK, T. W. Nov. 20, 1936, No. 31854. [Class 106 (i)] A machine for performing calculations involving non-uniform notations comprises means for entering an amount in such notation and coding means for converting the entered amount into an exactly equivalent amount expressed in a uniform notation in terms of an equivalence unit which is normally the lowest unit of the non.uniform notation or which is a sub-multiple of said lowest unit or is the product of said lowest unit or a submultiple thereof and a number whose prime factors are factors of the radix of the uniform notation. The coding is effected by summing the products obtained by multiplying each digit of the original amount by an appropriate factor selected from a series of such factors stored in the machine. The product or quotient result can also be decoded by selecting corresponding decoding factors. The coding and decoding factors are arranged in groups which can be exchanged for others depending on the nature of the computation involved. Keyboard. The machine is provided with banks of keys 30, of which the pence column is shown in Fig. la, each key stem is formed with teeth 32 engaging a gear sector 33 secured to a rocking bail 34. Each bail has a tooth 36 engaging a notch in a corresponding slide 35 and each slide, except the ones moved by a particular bail, has openings 38 with lugs 39 that co-operate with a tooth 40 on the bail to prevent depression of more than one key in any bank. The depressed key is locked by a pawl 42 engaging the displaced slide. The operated key and slide may be restored by depressing a key 30a co-operating through a bell-crank 47 with a pin 45 on an arm of the pawl 42. Each key stem is formed with lugs 50, 51 that co-operate with pins 52, 53 on a rocking lever 56 pivoted to a slide 55 having rack teeth in mesh with a sector secured to a shaft 48. When the shaft 48 operates to move the slide 55 to the right, the lever 56 will be rocked in one or other direction depending on the position of the key 30. If a key 30 is not depressed the lever 56 rocks idly counter clockwise, but if a key is depressed the lever rocks clockwise and by reason of its pin-andslot connection with a lever 57 rocks this lever about its connection with a pin 62 on a rocking lever 213 supported by a slide 217. In an entry from the keyboard the pin 62 normally engages a lug 211 on a slide 210. The lever 57 is centrally pivoted to a yoke 59 which is displaced when the lever is rocked to engage a clutch member 65 with a co-operating clutch member 67, secured to a shaft 66. Each clutch member 67 is provided with teeth 69 engaging a rack 70 ; there is one rack 70 for each horizontal row of keys and each rack receives from the driving mechanism of the machine a harmonic movement in accordance with the digital value of its row of keys. In addition to the banks of amount keys the machine is provided with banks of operation control keys 80, Fig. 6, each key having a tubular stem with an enlarged part 83 formed with helical slots engaging splines 88 on the end of a shaft 86. To each shaft 86 is secured a pinion 89, Fig. 2b, extending through an opening 90 in each of a number of plates 91. A group of plates 91 is arranged in one plane and there are as many co-planar groups as there are control keys. Only one plate 91 in each group is provided with gear teeth 98 to mesh with one of the pinions 89. When a key 80 is depressed the related group of plates 91, which are connected by a plate 92 at one end and bell-cranks 91a, 92a and a link 93 at the opposite end, are displaced so as to move a number of bars 101, Fig, 2a, pivoted to the plate 92. Each bar is provided with one or more teeth 102 adapted to engage projections on one or more long pinions 74, and are thereby rocked in accordance with the type of operation to be performed. Operating mechanism. The long pinions 74 co-operate with normally inoperative pinions 72, Figs. 3a and 5, and move selected ones into engagement with related racks 75. The racks 75 are reciprocated positively by bell cranks 78 with rollers engaging complementary cams 800, 820, mounted on the main operating shaft and impart movement through the pinions 72 to driving shafts 71 operating the various actuating members. Totalizing-counters. Secured on each of the differentially actuated shafts 66 are five bevel wheels 110, Figs. 1b, 7, and 9 one for each of the five totalizers 136. Each wheel 110 meshes with a pair of bevel wheels 111, 112, Fig. 8, on stub shafts and formed integral with spur gears 117, 121 in mesh with gears 118, 122. The gears 118, are provided with dog teeth 119 engaging one part 120 of a dog clutch and the gears 122 are similarly formed with dog teeth 123. A gear wheel 125 is mounted to rotate and slide on the hubs of the gears 120, 122 and is provided with teeth 126 to engage the teeth 123 and teeth 127 to engage teeth 128 on the clutch part 120. By this reversing mechanism the movement of the shafts 66 is imparted in one or other direction to the wheels 125. The wheels 125 are shifted by a bar 130 having ears 129 engaging slots in the wheels. The movement of the wheels 125 is transmitted by broad pinions 131, pinions 133 to pinions 135 on the numeral drums 136. In certain denominations of the sterling totalizer the gearing is modified. In the decimal totalizers the decimal point can be adjusted by rotating the shaft 136 which carries discs, each with a mark, the marks being arranged in spiral formation. Transfer mechanism. Each broad pinion 131 meshes with a transfer wheel 151 rotatable on a shaft 152, Figs. 7, 9 and 10, and provided with a single tooth 150 to impart a step movement to a mutilated wheel 169. To the hub of the wheel 169 is secured a mutilated wheel 168 which engages teeth 167 of a locking bar 164 of the next higher denomination, so that the bar is raised or lowered depending on the direction of movement of the transfer tooth 150. If the bar moves downwardly a projection 171 thereon moves to engage a roller 155b on a pivoted lever 155 and lock it against a frame member 162a. When a slide 159 carrying the lever 155 is moved to the left, Fig. 7, the lever 155 will rock clockwise and a tooth thereon will impart a step movement to a wheel 161 secured to the transfer wheel 151. If the bar moves upwardly a lug 172 locks a roller 156b on a lever 156 so that when the slide 160 moves a tooth on the lever 156 imparts a step movement to the transfer wheel in the opposite direction. If no transfer is to be effected the levers 155, 156 rock idly when the slides 159, 160 are operated. To permit of consequent transfer operations the slides of the various denominations are actuated in succession by the interconnection of links 401, 402, Fig. 1b, with links 407 operated by staggered cams on a shaft (not shown). After the transfer movements have been completed shafts 124, 134 are operated by a cam on this shaft and connections with a rack 408. Members 153 or 153a on the shafts engage the wheel 168 to restore the transfer parts to normal, the transfer wheel 151, 161 and the tooth 150 being slid lengthwise to move the tooth out of the path of wheel 169 by the movement of a bar 180. Zeroizing mechanism. By the movement of the bar 180 to the extreme left the transfer tooth 150 is moved into the path of a pin 183, Fig. 10, on a sleeve 182 keyed to the shaft 152 so that when the shaft is rotated through 9/10ths of a revolution the totalizer wheels are zeroized. At the same time a bar 186, Fig. 9, is shifted to bring stops 185 into the path of pins 184 on the numeral wheels. Reduction or coding and decoding factor retaining devices. Groups of representations of coding factors for the various denominations of each non-uniform notation are provided which can reduce or code the amount entered into an exactly equivalent amount in a uniform notation of which the unit is one of the units of the non-uniform notation. Two such equivalent amounts can then be multiplied and the resulting product can be reduced or decoded into one of the original notations. Examples of the operation of the machine with various coding and decoding factors are set forth in the Specification. The mechanism for this purpose comprises groups of shafts 233, Figs. 1c and 18, arranged in horizontal rows one row for each notation. Each shaft carries a plurality of discs 235 arranged in pairs for the various digits, and can be turned to any one of a number of positions by the step-by-step operation of a corresponding shaft 244; the discs have notches which in a particular setting represent the digits in the appropriate denomination of the factor. In this position, after the shafts have been moved to the operative position by the action of arms 250 on a shaft 249, the even numbered disc corresponding to the digit presents a notch to a lug 236 on a bridge piece 221 connecting two slides or reading members 210, 220 while the odd numbered discs of all the other pairs present their notches to the lugs of a bridge piece 224 connecting another pair of slides or reading members 222, 223. One slide of each pair, viz. the slides 220, 222, carry racks 225, 226 in mesh with a gear wheel 227 rotatable on a shaft 228 that is supported by means of an eccentric and strap 229 on a shaft 231. When the shafts 231 are turned through half a revolution the gear 227 tends to move the pairs of racks downwardly, but by reason of the notches only the slides 210, 220 corresponding to the required digit are lowered. By this means the lugs 211, 212 on the upper end of the slide 210 are set so as to free the pin 62 on the lever 213 of the slide 217 which is similar to the slide 55. When the respective slides 217 are moved by the operation of the shaft 218 the levers 57 pivot about the pin 52 and effect the engagement of the clutch parts 65, 67, in the same manner as on key depression. The shafts 233 corresponding to any group of factors c